I Built A Friend
by BlackIsMyMiddleName
Summary: AU where Tadashi is a single child and builds a robot to keep him company. Based off the song "I Built A Friend" by Alex Benjamin. Rated T for suicide.


**I Built A Friend**

**-A Big Hero 6 AU FanFiction-**

**Chapter 1**

**"Almost done... just...a little more..."**

**Screwdriver held in one hand, a 12-year-old Tadashi Hamada sat hunched over at the dinner table, parts and tools scattered all over the wooden surface as he worked. In front of him, the subject of his concentration was slumped in a cross-legged position with its head down and the port on the right side of it's head open. Oblivious to anything and everything not pertaining to his work, Tadashi didn't even notice when his Aunt walked into the room behind him and looked over his shoulder curiously. "So," She said, startling him almost out of his chair, "what are you working on **_**this**_** time? Another robot?"**

**Tadashi regained his composure (with some difficulty) and shook his head. "No. Not this time." He said, turning his attention back to his project. A few more adjustments were made, and then he was setting his tool aside and closing up the open port, saying as he did so, "He's more than a robot."**

**There was a soft 'click' as the port was shut. Tadashi leaned back a little to view the result of two days of work, then nodded in satisfaction. Getting up, he began clearing all the tools, wires, and various parts off the table into a shoebox. Aunt Cass watched for a second, then turned back to the small figure sitting, complete, on the table. It was shaped like a very small human (wearing an unusual purple armor-like outfit, but still). The face was remarkably life-like for a machine, but the eyes and mouth were shut. After looking at the figure for a few minutes, Aunt Cass glanced over at Tadashi. "He?" She inquired, one eyebrow raised. **

**Her young nephew nodded. "Yeah. He." He replied instantaneously, walking back over to stand in front of his creation. **

**"His name is Hiro. He's my new little brother." **

**Chapter 2**

**"Your little brother?" Aunt Cass repeated, rather surprised at her nephew's answer. Tadashi nodded. "Yep." He reached over and pushed a switch on the figure's back. A split second later he glanced up at Aunt Cass with a half-apologetic expression on his face. "I mean.. I know that he's not **_**really**_** my little brother, but..."**

**Aunt Cass put a hand on Tadashi's shoulder. "Honey, it's fine." Ruffling his short-cut hair, she smiled. "I think he'll make a great brother for you." **

**Tadashi's eyes lit up. "You think so?" He said. "Sure, it won't be the same as having a **_**real**_** person, someone who's literally my brother, but still." He looked back at his creation with a smile.**

**Hiro stared back at him.**

**Tadashi almsot fell out of his chair backward in surprise. Only Aunt Cass's speed saved him from collapsing to the floor as she caught the back of the chair. A second later Tadashi was up again, his eyes wide. "He works..." He said softly, looking at the little figure seated in front of him. After a moment, however, he noticed that Hiro had yet to move. Suddenly he wondered if he had miswired something. "Um... hello?" He said rather hesitantly, waving a hand in front of his creation's face. Hiro blinked, then turned his head and looked up at his creator. At first, his expression was completely blank. Then his eyes focused on Tadashi's face, and both his eyebrows went up simultaneously. **

**Tadashi grinned. "Hi, Hiro." He said, trying to contain his excitement. Hiro seemed to think about this greeting for a moment. Then a small smile appeared on his face, and he raised one hand in a wave. From where she was standing behind Tadashi, Aunt Cass waved back.**

**Chapter 3**

**"Hiro, can you see me okay?" Tadashi asked. Hiro tilted his head one way, then the other. He nodded. Then a look of confusion clouded his face. Tadashi was concerned as he watched his little brother stare at him for a moment. "What's wrong?" **

**"Why... are you so tall?" Hiro asked slowly, shaking his head and then looking up at Tadashi with a frown. Tadashi smiled. "'Cause I'm older than you. I'm twelve, and you're... one, I guess." He said. Gesturing behind himself at his aunt, he continued, "Aunt Cass is older than both of us, so she's taller than me."**

**Hiro looked over at Aunt Cass, then back at Tadashi. A second later, his expression brightened. "Ok, that makes more sense." He said as he moved to get up. Tadashi watched as his little brother stood up and looked around. He could practically see all the details and information he had painstakingly programmed into Hiro running through his little brother's mind. Finally Hiro looked at Tadashi again. "So...how do I get down?" He asked. **

**Instead of answering, Tadashi reached out and scooped Hiro off the table with both hands, lifting him down to the floor. "Sorry about that." The older brother said as he set Hiro down. "I should have though of that." Hiro shrugged, then paused as another thought came to him. Then he looked up at Tadashi, a mischievous expression in his eyes. "Now how do I get back **_**up**_** for mealtimes?" Tadashi looked around at the table and chairs, all of which were at least 5 inches taller than Hiro, and sighed. "Um... I don't know... maybe..." **

**Here Aunt Cass leaned down and patted Hiro's head. "We'll just have to lift you up here, simple as that." She said, smiling. When Hiro didn't look entirely satisfied, she added, "Or we can get a stepladder for you. Either way." Hiro nodded absently at this, then glanced down at his feet. "**_**Or**_**..." he said quietly, "...**_**rocket boosters**_**."**

**Chapter 4**

_**Three years later...**_

**"Ta! Da! Shi! Get! Up!" Hiro chanted, jumping up and down enthusiastically on his older brother's bed. Tadashi mumbled something unintelligible in return and felt around for his extra pillow. Already armed with said weapon, Hiro wacked Tadashi over the head with the pillow. "Come on already!" He insisted loudly. After a moment more of this one-sided pillowfight, Tadashi sighed. Sitting up slowly, he grabbed the pillow he had just a moment ago been using and knocked Hiro backwards onto the bed with it. "Alright already." He said slowly, rubbing his face in a bleary manner and glancing at his clock. **

_**9:43 a.m.**_

**"What?! Oh, you've go to be..." Tadashi exclaimed as he scrambled out of bed. "And on the weekend, even!" He added. Hiro giggled from where he lay on his back on the bed as he watched Tadashi collect up a set of clothes for the day and hs computer. "Maybe **_**next time**_**... you should pay attention to me when I..." Hiro started, only to trail off as Tadashi left the room. Hiro scowled, sitting up and folding his arms over his chest as he yelled after Tadashi, "Or not!"**

**Half an hour later, Hiro lay on his stomach on the twin-sized bed set up on his side of the room, playing with his own laptop. When Tadashi walked in, his little brother didn't even glance up. Instead, he continued playing, saying in what was meant to be a reprimanding tone, "You know, you're going to waste your whole life away by laying in bed all day." **

**Tadashi pretended to ignore this comment. Instead he made his way through the piles of random things laying all over the floor to the edge of the bed, where he stood looking over Hiro's shoulder until his little brother finally looked up in annoyance. "Why do you have to..." Hiro began again. Before he could finish, Tadashi reached over and grabbed the laptop, taking off out of the room and yelling back, "Come on, you're going to miss breakfast!"**

**Chapter 5**

_**That December...**_

**"Ta! Da! Shi! Get! Up!" **

**"Ugh...not again..." Tadashi groaned, rolling over in bed and burying his face in the pillows. "Why are you like this, Hiro?" He asked, his voice muffled by the pillow. **

**When he received no response, Tadashi lifted his head and looked around his room groggily for his little brother. His visual search proved fruitless, however, since Hiro had already left the room. Tadashi shook his head and rolled over again, sitting up and swinging both legs over the side of the bed as he yawned. **_**And to think,**_** he reminisced, **_**I used to be a willing part of such an **_**early**_** Christmas tradition.**_

**Tadashi reached the mid-level just as Aunt Cass was coming out of her room. He almost laughed in spite of himself at her appearance. Messy-haired and drowsy-eyed, she was wearing a loose-fitting San Fransokyo Ninjas jersey and sweatpants under her bathrobe, paired with fuzzy cat slippers. When she saw Tadashi grinning at her sleepily, she smiled. "I'm guessing my bedhead doesn't impress, huh?" She said with a yawn.**

**"Come on!" Hiro nagged, jumping up and down on the couch in front of the TV. "I'll bet you guys are just **_**trying**_** to take longer, aren't you?"**

**Tadashi walked into the living room and stretched slowly. "Well, now that you mention it... we **_**could**_**." He said, giving Aunt Cass a conspiratory look. She chuckled and shook her head. "Really, Tadashi? I always thought better of you." She said in a mock reproachful tone. Tadashi shrugged and smiled, then turned to Hiro with a look of false irritation. "Alright fine, knucklehead. You win."**

**Chapter 6**

**"Hmmmm..." Hiro muttered as he shook the present next to his head for the umpteenth time. "Hmmmm!" He hummed louder, purposefully not looking at Aunt Cass and Tadashi as he shook the package harder.**

**"HMMMM!"**

**"Oh, good grief, Hiro. Just open it already." Tadashi said playfully. Hiro pretended to glare at him for a split second before dropping all pretenses and ripping the present open with enthusiasm. Aunt Cass and Tadashi shared a congradulatory look as Hiro let out an exclaimation and pulled a high-quality tablet out of the box. After looking it over for about point 3 seconds, he looked sheepishly at the older two Hamadas. "Maybe I shouldn't have shaken it so hard..." He said with a goofy smile. At the sudden look of dismay on Tadashi's face, he hurriedly added, "It's not broken! I just... you know, **_**could**_** have broken it. If I had shaken it too hard. Maybe." He examined the tablet again, then smiled at his brother and aunt. "Thanks so much, by the way! It's awesome!"**

**Tadashi nodded. "You're welcome, kiddo." Then he leaned over and stage-whispered to Aunt Cass, "Maybe he'll be so busy with it that he'll let me sleep in. Hint. Hint." Here he gave Hiro a significant look. Hiro rolled his eyes and turned his attention to his next present. **

**Across the small room, Tadashi watched as his little brother opened gift after gift, each one hand-picked by either Tadashi or Aunt Cass. With every new electronic or gizmo, Hiro would exclaim enthusiastically, giving Tadashi a feeling of fulfillment at having so accurately predicted his little brother's wishlist. **

**Finally, Hiro set aside the last present and looked expectantly at his family. "Sooo..." He began, nodding pointedly toward the stockings hanging on the wall by the window. Tadashi faked a groan. "Seriously? You greedy little gremlin." He chuckled at the indignant look on Hiro's face, then got up and walked over to the window. "I'm just kidding, Hiro."**

**His little brother playfully punched Tadashi's leg as he set the packed stocking in Hiro's lap. Before the older Hamada brother could reach Aunt Cass with her stocking, Hiro was already tearing into his own with gusto.**

**Chapter 7**

**As item after item appeared out of Hiro's stocking, was subsequently admired and then carefully set aside, Tadashi and Aunt Cass set their own stockings to one side and watched the littlest Hamada's reactions. When at last he slowed down, there was only one item left in the stocking. Hiro flipped the stocking over and let the gift drop into his lap. "Hey!" He exclaimed, dropping the now empty stocking and picking up the present. "It's one of those Fitbit-GPS-watch things!" He held it up to examine it closer, then began strapping it onto his wrist. "Hey cool! It's a perfect fit!" He looked up happily. "Thanks, guys!"**

**Before either Tadashi or Aunt Cass could reply, Hiro jumped up, being careful not to step on any of his other gifts, and began walking around the room with his eyes glued to the device on his wrist. Tadashi chuckled. "So, you like your presents, then?" He asked with a smile. For answer Hiro stopped circling the room and all but threw himself into Tadashi's lap, hugging his older brother. Off to the side, Aunt Cass leaned over and wrapped her arms around the both of them. "Christmas-style group hug!" She said, making both brothers laugh. **

**Chapter 8**

**"So, how long are you going to... be gone?" Hiro asked in a dismal tone. Tadashi put the last of his notebooks in his bookbag and closed the top. "We've been over this, Hiro. I'll come home every day. It'll be just like when I was in highschool, just... I'll be gone for full days, not just a few hours." He leaned down and finished tying his shoes, then glanced back up at Hiro. His little brother was sitting on the edge of his bed, his short legs dangling over the edge as he stared at the floor despondently. Tadashi sighed. "Hiro, I... I know it seems like its not fair, but..." He paused, then walked over and sat down on the edge of the bed next to Hiro. "I have to go. If I don't, I'll never get a good enough education to qualify for a job anywhere."**

**Hiro finally glanced up, his face wearing the saddest expression he was capable of as he looked at Tadashi. "Then **_**don't**_**. **_**Don't**_** get a job. If you get a job somewhere, you'll **_**always**_** be gone."**

**Tadashi smiled and shook his head. "No, Hiro. That's not it at all. Besides, what if I worked **_**here **_**for Aunt Cass? That's an option, right?" He sighed again. "Look Hiro. I know this is hard for you. It's hard for me, too, though. You're my little brother. I'm going to miss you more than you miss me, alright? But I'll be home every night, I promise." **

**With that Tadashi got up and grabbed his bag and hat, then turned to the door. At the last second he glanced back over his shoulder. "Love you, Hiro. I'll see you tonight, okay?" Hiro nodded slowly. "Yeah. I guess."**

**When Hiro finally looked up again, Tadashi was gone.**

**Chapter 9**

_**Week 2 of college...**_

**Tadashi sat in his lab, absently tapping the desk with one hand as he read the sentence in front of him for the millionth time, having so far been unable to process the information for whatever reason. Finally he grunted, pushing back from the desk and letting his swivel chair slide across the room. By accident he pushed too hard, and the chair with him on board crashed into a cabinet, knocking a stack of files, scans, and blueprints onto the floor. "Come on..." Tadashi muttered as he got out of the chair and knelt on the floor to pick up the papers that lay scattered everywhere. After a moment, he paused. "What even **_**is**_** all this stuff?" He asked himself. **

**The next several minutes Tadashi spent sorting through the various papers into piles and folders. About halfway through, he paused and picked up a printed photo of him and his family. In the picture, he and Aunt Cass stood next to each other, with Hiro leaning on both their heads near the top. Everything about the picture looked stress-free and relaxed, from Aunt Cass's smile to Hiro's messy hair. Tadashi looked at the photo for a few minutes with a smile, then glanced around at the other half of the mess on the floor. **_**Stress-free sounds so nice right now,**_** he thought as he reluctantly set the photo aside and continued picking up and sorting papers and files. He became so immersed in his organization that he almost didn't hear the knock on his laboratory door.**

**Chapter 10**

**"Come in?" Tadashi said, the invitation also doubling as a question as he glanced up from his spot on the floor. A second later the door was pushed open from the outside, and a young woman entered rather hesitantly. She was very tall, clad in high heels and what was either a long shirt or a short dress, plus a lab coat. When she saw Tadashi kneeling on the floor surrounded by piles of papers, blueprints, and textbooks, she paused. "Oh, I'm sorry! Are you busy right now? I can come back later if you want..." She said quickly. Tadashi shook his head and got up. "No, it's fine. I'm actually kind of not busy. I mean, yeah, I'm busy, but it's not a legitimate kind of busy." Here he gestured to the mess. "I can clean this up later." **

**Upon hearing his response, the young woman looked relieved. "Oh. Ok then." She said. Tadashi gave her a curious look. "So.. what brings you to the unremarkable laboratory of one Tadashi Hamada?" He asked with a smile. The young woman laughed. "Oh, so **_**you're**_** Tadashi? Nice to meet you, I'm... well, my friends call me Honey Lemon." Here she held out her hand, adding, "Actually, I was originally looking for a Mr. Hamada, but I guess I found him." **

**Tadashi's curiousity increased. "Honey Lemon, huh? That's quite the interesting title, if you don't mind me saying." He said as he shook her hand. Honey Lemon smiled. "No, I actually get that a lot. But... back to why I'm in your lab in the first place." She looked at the floor for a second, then back at Tadashi, a slightly embarrassed expression on her face as she said, "I was wondering... if you could fix my computer? It's been acting weird, and then today it just won't turn on."**

**Tadashi nodded. "I don't see why not. I mean, I'm not a computer expert, but I do know a few things." As he walked out the door behind her, he asked, "Out of curiousity, though, why come to me?"**

**Honey Lemon shrugged. "Because I heard you were a robotics and electronics protege."**

**Chapter 11**

_**Riiinngg! Riiinngg!**_

**"Now who would call this late?" Aunt Cass wondered aloud as she set down her dishrag and went to answer the phone. Across the kitchen, Hiro paused what he was doing long enough to glance at the clock. **

_**10:32 p.m.**_

_**Wow, it's getting late. Wonder where Tadashi is? **_**Hiro thought to himself as he glanced over at Aunt Cass. She looked a little concerned, and Hiro wondered if she was receiving bad news. **

**"Oh... okay. No, that's fine, honey. Don't worry about Hiro and me. We'll just, you know, hang out or something. Yes. Okay. Love you too, honey. Bye." Aunt Cass sighed as she hung up the phone again. After a brief moment she brushed her hair back and looked at Hiro. "Okay, so Tadashi apparently has something big he's working on at the college, and he says he won't be home for a while."**

**Hiro couldn't help but look disappointed. "How long exactly is 'a while'?" He asked. Aunt Cass shook her head. "Just a few days. He says we can stop by any time we want, but he doesn't want to take a break and then end up getting distracted." **

**Hiro didn't say anything. After a moment he simply turned back to the dishwasher and resumed his duty of unloading the clean dishes. Aunt Cass watched him for a few seconds, then walked over and gave him a hug. "It's not like he's never coming home, Hiro." She said in a somewhat reassuring tone. "He's just busy. I'll bet he already misses us more than we miss him." **

**Chapter 12**

_**Buzzzt! Buzzzt! Buzzzt!**_

**"Hang on a sec, I'm coming." Tadashi said absently. A second later he facepalmed at the realization that he had been talking to his cellphone. With a sigh, he slid across the room on his chair and picked up his phone off the table. Glancing at the call history, he sighed again. **_**7 missed calls from home. **_

**"How did I miss that many calls?" Tadashi voiced his thoughts aloud, rolling back across the room to his desk, phone in hand. A quick glance at the clock was all the confirmation he needed. Dialing the number for the Lucky Cat took less than a minute, and a few seconds later he heard Aunt Cass's voice on the line. **

**"Hello? Tadashi?"**

**"Hey, Aunt Cass." Tadashi took off his hat and ran the fingers of his left hand through his hair as he tried to think of a way to apologize for not answering her calls. After a brief moment, he finally said, "Um... sorry I didn't answer earlier. I had my phone on vibrate and I just... well, I'm sorry."**

**"It's okay, honey. We all get busy sometimes, I understand."**

**Tadashi smiled a little. "Thank you. I needed to hear that." He said. Then: "So, any particular reason why you called me? Not that I don't appreciate your calls, it's just that.. you know."**

**There was a pause, and for a moment Tadashi wondered if maybe the call had been cut off. Then finally he heard Aunt Cass sigh heavily. "It's Hiro. He's been asking me when you're coming home. Says he misses you terribly." Another pause, and then she continued, "To be honest, honey, I'm wondering the same thing. How much longer will this project you're working on take?"**

**Tadashi looked around the lab. "Maybe another day. Then I'll be home, I promise." There was a brief silence, and then Aunt Cass's voice again. "Alright. I know Hiro will hold you to that promise, as will I." Tadashi nodded absently. "I know you will, and I won't let you down."**

**Chapter 13**

**Hiro sat on the couch in the mid-level staring blankly out the window. Aunt Cass was downstairs running the cafe, so he had some time to himself. Outside the window, cars and people moved back and forth, going about their daily routines. **

**Hiro sighed. **

_**Why doesn't Tadashi come home? **_**He wondered sadly. **_**He promised he'd be home every day... did he abandon us? Abandon me? **_**Hiro shook his head. **_**No, Tadashi wouldn't do that. I'm his brother, after all...**_

**This last thought trailed off as he suddenly remembered something. Being robotic, he had the ability to review all his memories from the time of his creation. One memory in particular leapt out at him in this moment.**

_**"I mean.. I know that he's not really my little brother, but..."**_

**The sound of Tadashi's voice played back in Hiro's head as he access the memory. **_**Not really his brother...**_** He thought to himself. **_**Why would he say that unless... unless he never really cared.**_

_**Unless he never cared.**_

**Chapter 14**

_**That evening...**_

**"Aunt Cass? Hiro? I'm home." Tadashi called as he walked through the front door of the cafe. **_**So good to be back... **_**he thought as he closed the door and walked toward the stairs. Not hearing any response from anyone, he sighed. **_**They must've already gone to bed...**_

**Making his way up the first flight of stairs, Tadashi found himself feeling a sense of satisfaction. The basics of his project were done. Now he could spend the weekend at home, rather than at the lab. He could hang out, maybe play video games with Hiro or help Aunt Cass in the kitchen. The idea made him smile.**

**Upon reaching the top of the stairs, his smile vanished completely.**

**The kitchen light was on, illuminating the scene he found awaiting him. Hiro was sitting slumped over on the dining table, looking like a rag doll with nothing to support it. **

**"Hiro?" Tadashi called softly, feeling a sense of pain rising inside of him as he set his school bag down on the counter and walked over to the table. "Hey, are you..." He said, then stopped when he saw the spilled glass of water laying on its side on the table. **

**"**_**Hiro!"**_

**Chapter 15**

**"Hiro! Talk to me! What..." Tadashi frantically picked Hiro up, trying in vain to get a response. Hiro's eyes were open, but they weren't focused. Tadashi tried flicking the switch on Hiro's back, but it did nothing. "Come on, Hiro..." Tadashi said in a panicked tone as he set Hiro on the table and waited for him to power up again. As he waited, he looked anxiously around the room, trying to distract himself from the reality he knew he had to face.**

**Hiro was gone.**

**Tadashi's eyes searched the room, finally coming to rest on the singular piece of paper resting on the table. Grabbing it, he felt his heart stop as his eyes scanned the page covering in Hiro's sloppy handwriting.**

_**Tadashi,**_

_**If you're reading this, I'm sorry. I just... I don't know. I guess I finally realized how little I matter. That I was never really a brother to you. Don't try to deny it; I heard you say the same. It's okay, though. I know that now, you should be happier without someone else nagging you to come home, or pulling you away from your work, or holding you back.**_

_**I'm not stable by myself, Tadashi. You made me realize that. But I guess I was never meant to be a permanent part of your life.**_

_**Don't miss me.**_

**For the first time in years, Tadashi cried himself to sleep that night.**


End file.
